Joseph van ruymbeke



UNITED STATES PATENT OFFICE.

JOSEPH VAN RUYMBEKE, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO WILLIAM F. JOBBINS, OF SAME PLACE.

PROCESS OF MAKING BASIC PER SULPHATE OF IRON.

SPECIFICATION forming partpf Letters Patent No. 453,137, dated May 26, 1891.

- Application filed June 20. 1890 Serial No. 856,139. (No specimens.)

v T on whom it may concern:

Be it known that I, JOSEPH VAN RUYM' BEKE, a subject of the King of Belgium, residing at Chicago, in .the county of Cook and State of Illinois, have invented a certain new and useful Improvem ent'in Processes of Making Persulphate of Iron, which is fully set forth in the following specification.

In the manufacture of persulphate of iron [0 from iron ore heretofore the ore has been treated by heating it with a mixture of sulphuric and nitric acid. This treatment produces a sirupy solution, which may be evaporated to dryness, if desired. :5 My present invention relates to a new process for obtaining this persulphate by treating with sulphuric acid only.

The invention consists, briefly stated, in treating pulverized iron ore with sulphuric acid under heat, whereby an acid sulphate is obtained, and then submitting the latter product to a high degree of heat, as will be here inafter specified.

I have discovered that if finely-ground hematite ore is poured into and thoroughly mixed with the proper proportion of sulphuric acid at about 60 Baum and at a temperature of from 250 to 300 Fahrenheit an energetic action takes place rapidly, attended by the production of considerable heat, and the material rapidly solidifies, giving ofi considerable vapor and usually assuming a grayish color. The gray color will always appear when the acid used is at or above 60 Baum and is heated to 300 Fahrenheit, or nearly this temperature. A weaker acid Will produce the same reaction, but when it falls below 50 Baum the action becomes very slow and it is necessary to heat it to a higher temperature than with the stronger acid, and below Baum it is almost impossible to obtain the reaction. The product is an acid sulphate containing also some free ore'and some free acid. I have also discovered that if this gray product, containing yet some free acid and some free oxide of iron, as stated, is submitted to a high degree of heat of from 380 to 500 Fahrenheit it is transformed more or less rapidly, according to the temperature, into a persulphate by the combination of the free ore partly with the free acid and partly with the acid sulphate. This product is somewhat basic and usually assumes a yellow color, though with some hematites the color is green.

It becomes very soft and pulverizes with great ease.

In carrying out my process a hematite ore analyzing, say, fifty per cent. of iron or its equivalent of alumina is first thoroughly dried and then ground toafine powder. This pulverized ore is mixed with sulphuric acid in about the proportions of about onehundred and fifty pounds of the ore and two hundred and fifty pounds of the acid at Baum. This acid must be previously heated to about 300 Fahrenheitsay from 250 to 300 Fahrenheitand the mixing must be done rapidly and thoroughly. The mixture is then thrown upon a suitable floor, preferably of iron, before it solidifies, in which position the reaction continues and the mixture solidifies on the plates of the floor in a few minutes. The purpose of throwing the mixture upon the floor before solidification is simply to facilitate the breaking up of the mass. This product is an acid sulphate with some free ore and some free acid, and, as already stated, is usually of a grayish color. This material is then broken in pieces and is properly crushed in order to facilitate the subsequent application of heat. The pulverized material is placed in a suitable revolving drum heated to about 500 Fahrenheitsay from 380 to 500 Fahrenheit. This application of heat is continued several hours, depending upon the quantity and temperature of the mass treat-ed. 1f the load of the drum be about two tons of the material and the temperature be kept at nearly 500 Fahrenheit, about six hours will be necessary to complete the operation and the time must be varied from this period according to quantity and temperature. Vhen completely cooked and the second reaction mentioned above as produced by this applition of heat is completed, the mass assumes a 9 5 substantially uniform yellow, or in some other instances green color, as stated above. It is a somewhat basic persnlphate of iron and is either in a pulverized condition, due to the revolution of the drum, or is readilypulverized by 1 0o reason of its softness. A solution of the acid sulphate obtained by the first reaction is yel low, while a solution of the basic per-sulphate obtained by the last reaction is red.

It is to be noted from the description above that my process relates to the treatment of natnraloxide. The action of the persulphate on ferric hydroxide is well known in chemistry; but this action is very different from that on an oxide, especially a natural oxide, such as iron ore. It is well known among chemists that hydroxide of iron is very easily dissolved by acids, whereas natural oxides are dissolved with difliculty, and in the case of diluted sulphuric acid are almost absolutely insoluble, even with a prolonged ebullition. Theknown treatment of ferric hydroxide referred to above will not effect with the natural oxide the result described above, while the process 4 herein set forth is entirely efficient and successful in the treatment of such natural oxide.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

The herein-described process of making basic persulphate of iron, consisting, in first mixing sulphuric acid with oxide of iron and then submitting this mixture to the action of heat at from 380 to 500 Fahrenheit until the water has been expelled and a persulphate of requisite basieity is produced, substantially 0 as described.

J OSEPII VAN RUYMBEKE.

Witnesses:

CARRIE FEIGELL, A. M. Bnsr. 

